A leaked build of Windows "Blue", aka Windows 8.1, also contained an early version of IE11. Web developer François Remy (http://fremycompany.com/BG/2013/Internet-Explorer-11-rsquo-s-leaked-build-395/) decided to see what it was hiding and found that there were WebGL APIs, but they were non-functional. Rafael Rivera, who writes the Within Windows blog, dug a little deeper and discovered the registry keys that have to be changed to enable WebGL support. Apparently the API works so well that you can take existing WebGL programs (with OpenGL shaders) and just run them. As the implementation also supports DirectX HLSL shaders it seems reasonable to guess that the implementation maps OpenGL to DirectX so avoiding Microsoft having to endorse OpenGL use. Microsoft may be embracing open source but not when it hurts its own products like DirectX."
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